Manufacture of nuts



March 5, 1935. J. w. GIBNEY 1,993,137

MANUFACTURE OF NUTS Filed Dec. 4, 1934 Patented Mar. 5, 1935 UNITED STATES PATENT OFFICE MANUFACTURE OF NUTS New York Application December 4, 1934, Serial No. 755,867

11 Claims.

This invention relates to the method of and means for shaping from cold stock semi-finish and double-cup nuts. Semi-finish nuts are commonly understood to be nut blanks which have one face chamfered and on the other face a washer effect resulting from flow of the metal, and double-cup nuts are well known to be nut blanks which have both faces chamfered.

The object of the invention is to provide a method and means whereby such nuts having maximum strength and commercially satisfactory size and finish can be produced economically and rapidly solely by compression with but a slight waste of stock and with a minimum wear on the tools.

In practicing this method pieces which have been cut from rolled bars and roughly formed into hexagonal shape are so presented to a succession of dies and punches that the finished faces are accurately formed by flow of the metal in the dies under the pressure induced by the punches rather than by machine facing, and the holes pierced across the grain rather than lengthwise of the grain of the metal. In accomplishing this the die cavities are so shaped and are of such size relative to the size of the blank, and the punches are so designed and caused to act, that there is always more or less breathing space or void which permits the desired lubrication of the dies and 30 punches and allows the necessary flow of the metal being shaped without producing an abnormal or undue expansion of the metal against the walls of the dies and punches, or excessive and 35 destructive condensing or deformation of the physical structure of the metal.

Figs. 1 to 8 inclusive of the accompanying drawing in sectional views show the tools employed and illustrate the effect of their actions on a hex- 40 agonal blank in producing a semi-finish nut, and Figs. 9 to 16 inclusive, are similar views'of the tools and their actions which produce a doublecup nut.

Fig. 1 shows a blank entered into the first die used in the shaping of a semi-finish nut and the punch about to act.

Fig. 2 shows the effect on the blank of the action of the first punch.

50 Fig. 3 shows the blank inthe second die and the punch about to act.

Fig. 4 shows the effect of the action of the second punch.

Fig. 5 shows the blank in the third die and the punch about to act.

Fig. 6 shows the effect of the action of the third punch.

Fig. 7 shows the blank in the fourth die and the punch about to act.

Fig. 8 shows the effect of the action of the fourth punch which completes the semi-finish nut.

Fig. 9 shows a blank entered into the first die used in the shaping of a double-cup nut and the punch about to act.

Fig. 10 shows the efifect on the blank of the action of the first punch.

Fig. 11 shows the blank in the second die and the punch about to act.

Fig. 12 shows the effect of the action of the second punch.

Fig. 13 shows the blank in the third die and the punch about to act.

Fig. 14 shows the efiect of the action of the third punch.

Fig. 15 shows the blank in the fourth die and the punch about to act.

Fig. 16 shows the eiiect of the action of the fourth punchwhichcompletes the double-cup nut.

The original blanks may be produced by the method disclosed in Patent No. 1,957,952 issued May 8, 1934, and the dies and punches may be arranged in such a machine as is shown in Patent No. 1,088,192 issued Feb. 24, 1924.

In practicing the method which forms the subject of this invention, whether for producinga semi-finish or a double-cup nut, as the first step a roughly formed hexagon blank 1 is fed into the hexagonal cavity of a die 2 and subjected to the pressure of a hexagonal punch 3 which has a conical teat 4. The cavity of this die is diametrically somewhat larger than the blank diameter and its side wall 5 is slightly tapered outwardly. Extending through the bottom wall 6 of the die, which has an angular surface '7 at the corner of the cavity, is a circular knock-out plug 8 with a dome-shaped teat 9. In this first step the punch pressure is enough to force the teats into the blank and expand the metal to the side wall of the die cavity but not sufiicient to entirely flatten the outer face of the blank, leaving a breathing space at 10, and not sufiicient to force the blank closely against the bottom of the die cavity, leaving a breathing space at 11, which spaces permit the metal to expand more or less, as it will owing to difierences in qualities or condition of commercial stock, without structural crush of the metal or destructive wear on the tools.

The blank thus produced, if a nut with a washer efiect on its bottom face is to be made,

is fed into a hexagonal die 12 and subjected to the pressure of a hexagonal punch 13. The

diameter of the cavity of this die is larger than the blank diameter and the side wall is tapered. The bottom wall has an angular shoulder 14 which provides an annular recess 15. The punch 13 has a conical teat 16 that is shorter than the teat 4 of the punch 3, and the knock-out plug 17 has a short circular teat 18. The pressure in this second step is suflicient to flatten the outer face of the blank and flow some of the metal into, but not necessarily to the bottom of, the recess 15. In this case owing to the shapes of the parts there are breathing spacesl9 at the end of the punch teat 16; 20 at the end of the plug teat 18; and 21 at the bottom of the recess l5;-which spaces permit of lubrication and metal expansion.

If a double-cup nut is to be shaped, the second step is the same as above stated for the semifinish nut. The punches and the knock-out plugs, and the pressures are the same. The dies are the same except that the cavity for the semifinish nut has the angular shoulder 14 which produces the washer effect, while the cavity for the double-cup nut has a sloping shoulder 22 which chamfers the face.

Following this the blanks of both shapes are treated alike. The blank is reversed and fed into a hexagonal die 23 with the top face toward the bottom of the cavity and pressure applied to the bottom face by a punch 24. The cavity of the die 23 diametrically is somewhat larger than the diameter of the blank, and its side wall is slightly outwardly tapered and has a chamfering surface 25 at the inner corner. Extending through the bottom of this die is an ejecting plug 26 with circular teat 27. The punch 24 used in this step preferably is circular and has a diameter but little larger than the diameter of the washer 28 or flat 29 on the bottom of the blank, and it has a circular teat 30 with a tapered surface 31 adjacent to the flat end 32 of the punch. The pressure in this case forces the top of the blank to the bottom of the cavity so as to form the chamfer 33, and expands the metal against the side wall. The punch also flows the Web 34 which separates the recesses previously produced by the teats, from near the bottom to near the top of the blank and at the same time bevels the opening into the bottom of the blank. Breathing voids 35 and 36 are left at the ends of the teats, and space 37 is left around the end of the punch to permit free expansion of the metal and relieve the tools from excess crushing strains.

The final step comprises feeding the blank, of either shape, into the cavity of a hexagonal finishing die 38 which has a straight side wall 39, a chamfering comer 40 and a tubular ejecting plug 41, and with a round punch 42 shearing the web 34, and completing the perforation which is subsequently threaded. The pressure resulting from this action causes the tapered wall of the blank to conform to the straight wall of the die cavity, smooths the chamfer, and causes the plug to flatten the top face of the nut.

As the cavities of the dies are somewhat larger than the blanks to be received and the walls, except that of the finishing die, are slightly outwardly tapered, and as breathing spaces or voids are left in all cases, not only can the contacting surfaces be efficiently lubricated and the blanks easily ejected, but the metal is gradually flowed to obtain the required shapes without its physical structure being crushed or its strength deleteriously afiected and without causing destructive effect on the dies and punches.

The foregoing description assumes that the dies are stationary and the punches movable, it is however within the purview of the invention to have the punches stationary and the dies movable for attaining the same result.

Forming the semi-finish and double-cup faces at the bottom of the dies, according to the instant method, eliminates the possibility of burrs and excess metal which necessitates machining for removal.

The invention claimed is:

1. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly shaping the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top face and further shaping the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses, smoothing the top face and expanding the blank transversely to finished shape.

2. The method of producing nuts which comprises, by pressure applied fiatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly shaping the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top faces and further shaping the bottom face, reversing the blank and by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses, smoothing the top face and expanding the blank transversely to finished shape.

3. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly chamfering the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top face and further shaping the bottom face, by subsequent pressure applied fiatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally by pressure, shearing out the web between said recesses, smoothing the top face and expanding the blank transversely to finished shape.

4. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly chamfering the bottom face, by a following pressure applied fiatwise again expanding the metal transversely, flattening the top face and raisin a washer on the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the washer face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses, smoothing the top face and expanding the blank transversely to finished shape.

5. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly chamfering the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top face and further chamfering the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses, smoothingthe top face and expanding the blank transversely to finished shape.

6. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly shaping the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top face and further shaping the bottom face, reversing the blank and by bottom face forming a chamfer on the top face and distorting the web between said recesses, and

Y finally by pressure shearing out the web between said recesses, smoothing the top face and expanding the blank transversely to finished shape.

7. The method of producing nuts which comprises, by pressure applied flatwise to a cold hex-' agonal blank, recessing the top and bottom races, partly shaping the bottom face and tapering the side faces, by a following pressure applied fiatwise, flattening the top face and further shaping the bottom face and continuing the tapering of the side faces, by subsequent pressure applied flatwise smoothing the bottom face forming a chamfer on the top face and reversely tapering the side faces, and finally by pressure shearing out the web between said recesses, smoothing the top face and squaring the side faces to finished shape.

' 8. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top andbottom faces, expanding the metal transversely and partly shaping the bottom face, by a following pressure applied flatwise again expanding the metal transversely, flattening the top face and further shaping the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses.

9. The method of producing nuts which comprises, by pressure applied fiatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly chamfering the bottom face, by a following pressure applied fiatwise again expanding the metal transversely and raising a washer on the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the washer face and forming a chamfer on the top face, and finally by pressure shearing out the web between said recesses.

10. The method of producing nuts which comprises, by pressure applied fiatwise to a cold hexagonal blank recessing the top and bottom faces, expanding the metal transversely and partly chamfering the bottom face, by a following pressure applied flatwise again expanding the metal transversely and furtherchamfering the bottom face, by subsequent pressure applied flatwise again expanding the metal transversely, smoothing the bottom face and forming a chamfer on the top face, and finally bypressure shearing out the web between said recesses. I

11. The method of producing nuts which comprises, by pressure applied flatwise to a cold hexagonal blank recessing the top and bottom faces, partly shaping the bottom face and tapering the side faces, by afollowing pressure applied fiatwise, flattening the top face and further shaping the bottom face and continuing the tapering of the side faces, by subsequent pressure applied flatwise, smoothing the bottom face forming a chamfer on the top face and reversing the tapering of the side faces, and finally by pressure shearing out the web between said recesses.

JOSEPH W. GIBNEY. 

